Technical Field
This invention relates to optical stacks including one or more transparent conductors, and in particular to protecting such optical stacks from damaging electrostatic discharges.
Description of the Related Art
Optical stacks are used in applications requiring optical clarity and transparency, such as touch sensitive display surfaces where electrical conductivity is needed for touch sensitivity and optical clarity is needed for display clarity. Frequently, such optical stacks include a number of layers that include a substrate layer, a transparent conductor layer, and a protective overcoat layer. Optical stacks are manufactured using various manufacturing processes, including roll-to-roll production in the form of a continuous film.
Despite proper grounding of the roll-to-roll production equipment, it is possible for damaging levels of electrostatic charge to build up on or within the optical stack during production. Such electrostatic charges can propagate through the transparent conductor layer of the optical stack, causing structural damage to the transparent conductor layer if the resulting electrical current is too high.
Accordingly, there remains a need in the art to prevent the formation of damaging levels of electrostatic charge in optical stacks containing transparent conductors and/or to dissipate or mitigate the effects of damaging levels of electrostatic charge within an optical stack without damaging the transparent conductors within the optical stack.